Are you aware of the forums policy on giving answers to questions that could contribute to your final mark?

Sep 16th 2010, 07:55 PM

Zanderist

I'm not asking for answers.

I only ask about the bases, because I'm looking for some confirmation.

I will be doing the final answers, I want to do the final answers. I don't want anyone to have the glory of finding the final answer but me.

I just want to make sure that my methods are correct, that I'm heading in the right direction.

If you'd like I'll just go on what I'm thinking and post if it didn't work.

Sep 16th 2010, 07:59 PM

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Quote:

Originally Posted by Zanderist

I'm not asking for answers.

I only ask about the bases, because I'm looking for some confirmation.

I will be doing the final answers, I want to do the final answers. I don't want anyone to have the glory of finding the final answer but me.

I just want to make sure that my methods are correct, that I'm heading in the right direction.

If you'd like I'll just go on what I'm thinking and post if it didn't work.

Regarding question B, my opinion is that the problem is not well stated. We are given that the shaded region has area A. Then we are asked to estimate. But we should give the answer in terms of A and there should be no estimation.

The problem says "estimate" and there can be many equally good estimates to such a value. I might suggest using, not the area of a semi-circle, but the area of a semi-ellipse. If an ellipse has semi-axis lengths of a and b, then its area is and the area of half an ellipse is . The base across the parabola has length 2 so the semi-axis is 1. The depth of the parabola is 1 so that semi-axis is 1.

However, on a closer look I see that the problem says "If the vertical red shaded area in the graph has area A" which makes me think you are supposed to give an answer in terms of "A", not actually find A. But then they wouldn't say "estimate" would they? I agree with undefined that B is not well defined.

Caution- the parabola is also below the x-axis.

Since -8+ 8= 0, I think it would be worth using one of your attempts to answer "-A"!